Road Weather Information System (RWIS)

Road Weather Information System (RWIS)

Have you ever noticed equipment next to a highway, which looked like a small weather station, and wondered about its purpose?

These “weather stations” are called environmental sensor stations (ESS). A network of ESS make up a road weather information system (RWIS). The North Dakota Department of Transportation (NDDOT) is one of many state DOT’s across the country which utilizes RWIS as a tool to obtain road weather information and aid in decision making.

An ESS contains sensors which measure atmospheric and pavement conditions at locations across North Dakota. Here are some examples of data which can be obtained from ESS:

Atmospheric data:

Air temperature

Relative humidity

Visibility distance

Wind speed and direction

Precipitation type and rate

Radiation

Barometric pressure

Pavement data:

Pavement temperature

Pavement condition (Ex: wet, icy)

Pavement friction

Pavement images

Subsurface temperature

Environmental sensor stations are also available for public use. Click the link on this page to view the NDDOT RWIS map. ESS will appear as triangles on the RWIS map, as shown in the image below.